Enzymes Applications in Food Industries Enzyme Structure Enzyme

Enzymes Applications in Food Industries

Enzyme Structure

Enzyme Purification procedures Methods of enzyme purification 1. salt precipitation 2. Chromatographic methods i. ion exchange – cationic or anionic separation based on charge; the greater the net charge, the more strong the interaction; elute by increasing ionic strength of buffer or altering p. H ii. gel permeation (size exclusion) chromatography: separation based on size; larger proteins elute first

iii. hydrophobic interaction chromatography: separation based on hydrophobicity of protein surface; elute by decreasing polarity of buffer; more hydrophobic bind more strongly and elute last. iv. affinity chromatography: separation based on specific biological interaction; eg enzyme –substrate recognition; elute with substrate

v. immunoaffinity chromatography: separation based on specificity of antibody recognition of peptide sequence; elute by lowering p. H to 2 -3 to disrupt antibody – peptide interaction. Neutralize quickly to avoid loss of activity.

Assessment of purity SDS polyacrylamide gel electrophoresis enrichment N-group analysis Units of enzyme activity Activity: amount of product produced per unit time (eg. ? mols / sec)

Specific activity: amount of product produced per unit time per mg protein (eg. mmols / sec / mg) Enrichment: SA of fraction / SA of starting material Maximum possible enrichment: 100 / % of total protein represented by protein of interest % purity: actual enrichment / maximum possible enrichment % recovery (yield): total activity of fraction / total starting activity 10

Enzyme Immobilization